Question

如果已经有“可用”卷，我试图在启动配置中添加“if”条件以跳过添加新EBS卷。所以我想要实现的逻辑是，如果下面的检查变量为Null，则添加新的卷，否则跳过因为我将从用户数据中添加“可用”卷。 $ check = Get-EC2Volume -Filter @ {Name =“status”;值=“可用”}

BlockDeviceMappings:
        - DeviceName: /dev/sda1
          Ebs:
            VolumeType: gp2            
            VolumeSize: '100'
        !if $check              --> not sure how to put if condition here 
        - DeviceName: /dev/sdb   
          Ebs:
            DeleteOnTermination: "false"            
            VolumeSize: '50'
            VolumeType: gp2                 
        - DeviceName: /dev/sdc
          Ebs:
            DeleteOnTermination: "false"            
            VolumeSize: '50'
            VolumeType: gp2

Answer 1

以下是如何添加条件的示例代码

            BlockDeviceMappings:
            - !If
                - IsNeedVoume
                - DeviceName: "/dev/xvdcz"
                  Ebs:
                    VolumeSize: !Ref InstanceDockerVolume
                    VolumeType: 'gp2'
                - !Ref AWS::NoValue

Answer 2

您可以创建一个条件，即 AddEDrive ，用于检查是否指定了参数 EDriveSize 。如果是，那么它将创建BlockDeviceMapping，否则，什么也不做。

根据documentation：

/dev/sda1是DeviceName的推荐C:\

对于所有其他附加驱动器，建议/dev/xvd[f-z]

DeviceName。

AWSTemplateFormatVersion: '2010-09-09'
Conditions:
  AddCDrive: !Not [!Equals [!Ref CDriveSize, '']]
  AddDDrive: !Not [!Equals [!Ref DDriveSize, '']]
  AddEDrive: !Not [!Equals [!Ref EDriveSize, '']]
Parameters:
  CDriveSize: {Default: '', Type: String}
  DDriveSize: {Default: '', Type: String}
  EDriveSize: {Default: '', Type: String}
Resources:
  Instance:
    Properties:
      BlockDeviceMappings:
        - !If
          - AddCDrive
          - DeviceName: '/dev/sda1'
            Ebs:
              VolumeSize: !Ref CDriveSize
              VolumeType: gp2
          - !Ref AWS::NoValue
        - !If
          - AddDDrive
          - DeviceName: '/dev/xvdf'
            Ebs:
              VolumeSize: !Ref DDriveSize
              VolumeType: gp2
          - !Ref AWS::NoValue
        - !If
          - AddEDrive
          - DeviceName: '/dev/xvdg'
            Ebs:
              VolumeSize: !Ref EDriveSize
              VolumeType: gp2
          - !Ref AWS::NoValue

如果条件在BlockdeviceMapping中

2 个答案: